1. Field of the Invention
The invention pertains to a hydraulically damping rubber bearing consisting of an inner part, an outer part a certain distance concentrically or eccentrically outside the inner part, and a rubber part held between the other two parts, at least one damping medium-filled chamber being provided in the rubber part.
2. Description of the Related Art
Rubber bearings which consist of an inner part, an outer part a certain distance concentrically or eccentrically outside the inner part, and a rubber part between the other two parts, in which at least one damping medium-filled chamber is provided, are already known (e.g., GB 2 342 422). In this rubber bearing, the inner or outer part work together with a tubular component and an additional elastic rubber part to form an additional bearing, which works either in parallel or in series with the first bearing. In a rubber bearing of this type, each of the two individual rubber bearings has different tasks to fulfill; by fitting one of the bearings inside the other, a complete bearing assembly is created. Cylindrically designed hydraulic bearings as well as cylindrically designed rubber bearings allow only a limited degree of cardanic deflection. Any deflection angle beyond this leads necessarily to the destruction of the rubber bearing.
The object of the present invention is to develop a hydraulically damping rubber bearing in such a way that cardanic loads can be easily absorbed by the bearing.
According to the invention, an additional tubular part is provided a certain distance concentrically inside the inner part. A certain area of the outside surface of this tubular part is at least partially spherical, and a certain area of the inside surface of the inner part is also at least partially spherical. An elastic element is provided between these two spherical areas to form a rubber bearing.
It is advantageous that the different tasks of the bearing are divided, in that the hydraulically damping rubber bearing takes care of the hydraulic tasks, while the elastic element takes care of the cardanic loads, which hydraulically damping rubber bearings can handle to only a limited extent.
In accordance with another essential feature of the invention, it is provided that the elastic element has an approximately uniform wall thickness in cross section.
According to one design, it is provided that the additional tubular part can be cardanically deflected with respect to the inner part.
So that the rubber part can be mounted in the chassis of a motor vehicle, the outside surface of the additional tubular part is at least partially spherical, and a cylindrical bore passes axially through the center of the tubular part.
Another design provides that the cardanic deflection is absorbed by the elastic element.
Another embodiment provides that stops extending in the radial direction are provided between the inner part and the outer part. It is advantageous here not only that the stops are effective in the radial direction but also that they become effective even after small cardanic deflections. In accordance with another advantageous embodiment, it is provided that the rubber bearing is mounted vertically in the wheel suspension of a motor vehicle. The advantages here are that large cardanic deflections can thus be absorbed and that, via the hydraulically damping rubber bearing, the wheel oscillations can also be absorbed, so that the required durability is ensured.
According to another embodiment, it is provided that the rubber part and the elastic element can be made of different materials.
Another feature provides that the elastic element is tightly connected to the inner part and/or to the additional tubular part.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.